Furnace



Oct. 16, 1923. 1,470,876

J. REID FURNACE Filed aan. 5o. 192:5

/N VEN TOR 3y y TTG/WYE Y Patentedct. l5, 1923s `i Y FURNACE; f i

i s y`Jlppnwauon filed January 3o,- 19'23. serial iro.' s15,s97. i

f of Which the following is afspecification.

In. thecinnloustion of fuel ,on the grate of 'a steam looiler furnace is found, with natural draft, that, owing to insufcient'air, com# hustion is very sluggishat` some parts of i:the grate, V moreespeciallythe. front part,

tion. i

.and at other parts of the grate, especially towards the hack and in places,Where holes'y orthin patches occurin the fuel hed,Y an .amount'ofair passes through the grate` in excess f of that required for effective vc-onihustion. `Similaifconditions obtain With :forced draft and,k though .forced draft enables a f higher general .rate offcomhustion tofloe ohtainedjvith the sameheight ofgchininey or funnehthe amount ofairdriven through theV grate exceeds `that Yrequired forV combusjA' VThe; object of `theipresenti*invention to `i partof the grate which canfhe readilylitted provide means vfor directing air tothe front in: existing furnaces provided with 'hollow forced draft fronts. Thek saidm'eans comprise. acasting with longitudinal vdivision plates and-floor plate rand adapted to Vhe holted into an existing hollowffurnacefront so .as to .extend across thesaid front fand through the ashpitfopening fin the Ahack lthereof and under the furnace dead plate,

the arrangementheing such thatlair vfed-hy ka fan or equivalentfthrough valves into the furnacelfront in the usual Way is largely caught-by the said means and directed there oy through the front part of Atheffurnacej i the stokehold into the ashpit, the -usual door' heing removed.l By shutting'off 'the fan the Y grate, While the remainder of the grate receives air 1from the ash-pit, these supplies Y of air giving an adequate and approximately correct amount of air for p ropercomhus` tion; Vthe airipassing to the grate through the ashpit maybe supplied by thefan or equivalent, or may he admitted thereto Afrom the stokehold, the chimney or funneldraft being sulficientto draw the air through the grate.

The accompanying ydrawings show lan or-k dinary type of'boiler furnaceadapted for 'l carrying out the invention, Fig. fleeing a longitudinal section andl Fig.y 2 across section through the furnace'frontvillustratingy one arrangement Figs; 3 andeare fragd mentary vievvsfisimilaJ modified arrangernent.;r` 1 ,Y Y ,i Y.

The furnace tube a is ittedvvith a grate b,

dead plate c, bridge d, and a hollowjforced krdraft furnace front e as usual; the front shown has top and side airvalvesandan Vair cooledfhaiile aroundithe `firing opening as Well understood. i. In orderV to direct -air through ,the front part of the grate there isholted to thebaclr plate e1 ofthe front a casting fvvhich pro` jectshorizont'ally beneath the dead plate o JoHNaErD, or LONDON, ENGLAND v r te 'rigs'. 'raad 2 'of a throughthe lupper'part of the ashpitppene therefrom a numberfof vlongitudinal division jing ofk thfe'fronty and which` has depending i plates kj1, f2 forming: channels which are' kolosedat the bottom by aoor plate gfivhich extends to the front plate e2 ofthe front; f

the' centre division plate f1 extending nearly to the said front" plate 'and the plates f? von f each lside thereof tou successively lessl distances so thatV fan air flowingjthroughthe valvesof the front reaches the severaljchannels fin;v adequate quantity and is directed Without material floss ofvelo'city directlyto the `front, end of the grate. The o'or plate niaygloe kextended beneath the grate yby an attached upwardly cur ved"portion gli as slio\ vn. r `The pressure of the airis less than `that usually employed and to enable the pressure toheflept low7 air heaters in the 1 uptakes are dispensed with or so'constructf sonas to cutfolffthe fan draft air from they ed asto `offer'little obstruction.; `In practice7 the fan 'is run so that theA funnel can maini Vlower part,'throughfwhichjair yWill flovvgfrom' air at comparatively low pressurev or under forced draft. ,f v

In some places the dead plate c and the fan to, the yashpit and fitting an ashpit door, Y the furnace can hel Worked entirely With fan f' top .casting fmay he. slotted or perforated- "so, as to cause energeticcomhustionof the fuelY close up to theffurnaee front,- and, in

new Work it is ypreferred to rshortenthe casts ing and fit a steeply sloping slotted dead plate `and ylowerY the front end of tlie'grate,

thereby ensuring that a good Supply lo" fan air is delivered into the extreme `front end portion of the fuel bed.

curved air directingvplate is fitted against `the bridge support so as to smoothly direct i VAi5 recting device 'comprisling-` a 'castin longitudinal 4`dlvisioi'r*plates anda floor air towards the grate. fn y As a further modification thek arrangenient shown" in Figs. 3 and'4 .inay be adopted where the bottom or iioor plate g1 is movable 'about a hinge'gl." The lower edgee oi 'the division platee f, 70422 in this case are 'not straight but shaped soniewhat as ,Shownk so that the plate g1, which normally occupies the poeition `illuetratedin Fig. 3, may be lifted atthe front edge about the liinge,the`reby giving ino'refclearance when clearingout ashes and heldin vsuch position to vary'the lprogortionV oi: air passing'up through the iront `part .of the grate. j are )plate members carriedY by the plate g1' ,andl arranged closelyffadjacentto the channel walls of the casting fr" to normally complete such channelS and still to be tilted.`

l/Vhat I'claiin ist l *y i 2,1.- Ina steam boiler furnace having a hollow iront,` grate ash-pit, van airldiallow the fplatc'r, g1

plate adjustable with respect to said castiiigand removably secured in said' hollow iront so as toeXtend inwardlvffroni `the 4front'thereof into and partially through the ash-pit opening in the back thereof, thus dividing the space between the 'grate "and the bottom of the ash-pit, ubstantially 'las deecrib'ed.,v

2. In steam floor 'plate adapted to be removably secured ,A inf said hollow front sonas to extend in- Iwardly from theiiront thereof .into 'and par- 1K5,01tia-lly` throughthe ash-pit opening yin the backjthereof, eaidfiioorfplate being pro- "videdwith an'yarcuate extensionV and divicl-V ne the baci; @ne of the ashpt' e 'suitablyl g with `boiler Vfurnace having a hollow front, grate Vand ashpit, an air di- Y recting `device c`oniprising a casting with'` :l flongitudinal divisionjplates of= different ,145 lengths and an independently adjustable tween the grate vand thel bottoni of the ash:

pit, and an apertured deadplate .arranged aboveV the Hoorfplate, substantially as described.' f n 4.y ln a Steam boiler furnace, the combinaN ytion of a Yhollow furnace front, grate and ashpit and an directing ,device comprising a top plate extending from theback plate of theholloiv -frontinto the asghpit of the 'fur'- nace, an adjustable Subj acent'locr plate, re-

fniovably secured in fsaidy hollowrfrontand extendingv forwardly across the"i furnace' 'front and backwardly'r'through the ash-'pit division platesfbetweenfeaid top and floor plates extendinginto the hollow furnace front, the spaceS between .thej longitudinal Y f division plates being fopen wat fthe top within the' area ot the furnace front, Sub- {Stantially as described.

5". In a Steain boiler furnace, the 'co'inbination of'a holloii7 furnace front, grate anid prising a top` plate extending `ifi'oni'tlie'fback plate of` the hollow front intothe ash-pit of' thehfurnace, an adjustable eubjacent floor plate `removably vsecured in said' hollow front and extending :forwardly acro: .tlie

Vzurnacer front and baclrwar'dly throughl 'there ash-pit opening in said back plate 'and vyond the top LAplatei and longitudinal divil sion plates between `Said top andlii'oor vplates extending intothe:hollowfurnafce iront, the spaces between lthe longitudinal division plates- Ibeingopen at the, top f within rthe described.'

larea ofthe furnacek front',.Substantially as signed attendo@ reggiana, nella Cuff of January, r1923.` i Y yash-pit andan airk directing ,device corn- 

